Document Type |
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Article In Journal |
Document Title |
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Synthesis and adsorption performance of Mg(OH)(2) hexagonal nanosheet-graphene oxide composites Synthesis and adsorption performance of Mg(OH)(2) hexagonal nanosheet-graphene oxide composites |
Subject |
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physics |
Document Language |
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English |
Abstract |
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A series of Mg(OH)(2) hexagonal nanosheet-graphene oxide (GO) composites were synthesized
through a simple hydrothermal method using magnesium nitrate and GO as precursors, sodium nitrate
and sodium oxalate as additives, and sodium hydroxide and ammonia as precipitants. The as-prepared
samples were characterized by X-ray diffraction, nitrogen adsorption-desorption isotherms, Raman
spectroscopy, zeta potential analysis, and scanning electron microscopy (SEM). The adsorption affinity
of the as-prepared samples toward congo red (CR) in water was analyzed and investigated. Results
indicated that GO addition influenced the thickness, morphology, and adsorption performance of
Mg(OH)(2) hexagonal nanosheets. As GO concentration increased, the thickness decreased.
Especially at high GO concentration (1 wt%), Mg(OH)(2) hexagonal nanosheets changed into
aggregated flower-like spheres. Addition of small amounts of GO also increased the adsorption
capacity of Mg(OH)(2). The equilibrium adsorption data of CR on the composite were further
investigated by Langmuir and Freundlich models, indicating that the Langmuir model was much more
suitable for the experimental data. The sample prepared with 0.5 wt% GO showed the highest
adsorption capacity with 118 mg g (1). The experimental data were then fitted using pseudo-second
order kinetics, suggesting that pseudo-second order kinetics could well describe the adsorption of CR
on composites. Adsorption thermodynamics analysis showed that the adsorption activation energy was
29.2 kJ mol(-1), suggesting that the adsorption of CR onto the samples was physical adsorption.
Adsorption between the samples and CR was mainly due to the strong electrostatic attraction between
them because they had opposite charges. These findings indicated that Mg(OH)(2)-GO composite was
an effective adsorbent for the removal of CR in water |
ISSN |
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0169-4332 |
Journal Name |
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APPLIED SURFACE SCIENCE |
Volume |
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332 |
Issue Number |
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1 |
Publishing Year |
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1435 AH
2015 AD |
Article Type |
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Article |
Added Date |
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Monday, August 21, 2017 |
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Researchers
M.D Liu | Liu, M.D | Investigator | Doctorate | |
B Cheng | Cheng, B | Researcher | | |
W.K Ho | Ho, W.K | Researcher | Doctorate | |
J.G Yu | Yu, J.G | Researcher | Doctorate | jiaguoyu@yahoo.com |
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